Opteo spotted a negative keyword that blocks one or more of your own keywords, so they can't get impressions. For example, a broad match negative free blocks the keyword "gluten free pizza".
What pushing it does
Depending on what you choose, pushing does one of two things:
Remove Negative: deletes the negative, so the blocked keywords can serve again. Other searches it was blocking can start showing your ads too.
Pause Keyword: pauses the blocked keywords and leaves the negative in place.
Before you push
Check the Conflicting Keywords table, then pick Remove Negative or Pause Keyword from the menu.
Dismiss it if the conflict is intentional.
Covers Google Ads.